Pressure vessels are utilized in many industries for manufacturing products when maintaining specific temperatures and pressures is required. Industries using pressure vessels include but are not limited to pharmaceutical, chemical, food and beverage, medical, biotechnical, ethanol, dairy, water treatment, paper, cryogenic, and other industries requiring chemical or biological processing in a pressurized environment. The processes that require the use of pressure vessels often require instrumentation and other devices to measure and control operating conditions such as temperature, pressure, liquid level, and other parameters through various known instrumentation. Further, these industries may also require pressure vessels to have inlets, outlets, or ports to introduce or remove contents, obtain samples of the contents of the tank while maintaining a sterile or sealed environment, or perform other related actions.
Connections utilizing a retaining ring to hold instrumentation and other devices in sealed connection with a base mounted to a pressure vessel are well known in the art. In many cases, the instrumentation and devices are configured such that a solid (i.e., continuous and non-split) retaining ring is not able to slide over the entire instrumentation or device. In such cases, it has become common to use a split retaining ring constructed of two or more sections.
Split retaining ring connections, such as the NovAseptic® connector and the ASEPCONNECT™ connector, are well known in the art and utilize a base welded to the pressure vessel and a split retaining ring. The instrumentation is secured to the base by the split retaining ring that, when tightened, engages the instrument's ferrule and compresses the ferrule and an elastomeric seal against a seat in the base thereby effectuating the connection. The compression required to create the seal and connection is created using four or more threaded fasteners or bolts that can be tightened to achieve a desired compressive force and resistance.
A large number of pressure vessels manufactured and in use today are outfitted with bases designed for utilizing split retaining ring connections. A shortcoming of the prior art bolted split retaining ring connection relates to the thickness of the split retaining ring itself. The two or more sections of the split retaining ring act independently of one another. Because the split retaining ring sections act independently from one another, the bending forces exerted on the sections' free ends require the ring to be of an increased thickness, as compared to a solid ring, in order to meet certain industry codes, regulations and/or standards. The split retaining ring's increased thickness often presents clearance issues with the instrumentation and devices held in place by the split retaining ring. For example, the instrumentation and devices will sometimes have wires, fittings, couplings and other items extending therefrom that are obstructed by or in interference with the split retaining ring.
Therefore, a need exists for an improved split retaining ring having a reduced thickness to decrease the total depth of the pressure vessel connection so as not to interfere with or obstruct the instrumentation or device the split retaining ring is holding in place. A need also exists for a split retaining ring that has the strength characteristics similar to those of a solid, continuous ring. A need further exists for a split retaining ring that has increased strength characteristics so that it can be manufactured from a smaller amount of material.